A wireless communication system may be operated in various transmission modes, for example, a diversity mode, a Multiple-Input and Multiple-Output (MIMO) mode, and the like. A reception mode of a receiver may vary depending on a type of transmission modes. Accordingly; information regarding the transmission modes needs to be shared between a transmitter and a receiver.
Additionally, the wireless communication system may used a plurality of available frequency bands. Information on currently used frequency bands, and information on unused frequency bands need to be shared between the transmitter and the receiver.
Furthermore, the transmitter and the receiver may share a variety of information, as well as the above-described information. However, to share the above-described information, the transmitter may request information bits corresponding to the information. The information bits may function as an overhead in a communication system.